CN114270546A

CN114270546A - Flip-chip light emitting diode and light emitting device

Info

Publication number: CN114270546A
Application number: CN202180005001.3A
Authority: CN
Inventors: 刘士伟; 徐瑾; 张中英; 石保军; 王水杰; 刘可
Original assignee: Xiamen Sanan Optoelectronics Technology Co Ltd
Current assignee: Xiamen Sanan Optoelectronics Technology Co Ltd
Priority date: 2021-11-19
Filing date: 2021-11-19
Publication date: 2022-04-01
Anticipated expiration: 2041-11-19
Also published as: CN114270546B; WO2023087236A1; CN116895719A

Abstract

The application discloses a flip-chip light emitting diode and a light emitting device, wherein the flip-chip light emitting diode comprises a substrate and a semiconductor light emitting unit positioned on the substrate; the semiconductor stacking layer area with the function of the thimble is reserved at the central area of the flip-chip light-emitting diode to form a semiconductor island structure or a convex part, the area where the semiconductor island structure or the convex part is located is flat as the action area of the thimble, and when the thimble acts on the area, the risk of puncturing or bursting the protective layer is reduced.

Description

Flip-chip light emitting diode and light emitting device

Technical Field

The present application relates to the field of semiconductor technologies, and in particular, to a flip chip light emitting diode and a light emitting device.

Background

The flip-chip light emitting diode has the characteristics of high light emitting efficiency, energy conservation, environmental protection and long service life, and is widely applied to various fields such as illumination and backlight. When the existing flip-chip light-emitting diode is packaged, a thimble is required to act on a certain area of the front face of the flip-chip light-emitting diode so as to jack the flip-chip light-emitting diode and carry out die bonding, and the acting area of the thimble is often the central area of the front face of the flip-chip light-emitting diode.

The front surface of the flip-chip light emitting diode comprises an epitaxial structure, a transparent conducting layer, an electrode, and a protective layer and a bonding pad for protecting the epitaxial structure, the transparent conducting layer and the electrode, wherein the protective layer is usually made of a silicon oxide material or a distributed Bragg reflector formed by combining silicon oxide and titanium oxide.

Due to the brittleness of the protective layer, when the thimble acts on the front surface of the flip-chip light-emitting diode, the thimble is easy to puncture or break the protective layer to expose the epitaxial structure, the transparent conductive layer or the electrode below, so that the flip-chip light-emitting diode is easy to have the leakage failure phenomenon and the reliability of the flip-chip light-emitting diode is influenced.

Disclosure of Invention

The utility model aims at providing a flip-chip light emitting diode, its setting and the spaced semiconductor island structure of semiconductor luminescence unit, this semiconductor island structure area is as the effect region of thimble, can avoid the thimble to puncture or break the protective layer of semiconductor luminescence unit department to avoid flip-chip light emitting diode to appear leaking the electric failure phenomenon, improve flip-chip light emitting diode's reliability.

The application aims at providing a first flip-chip light emitting diode which comprises a substrate and a semiconductor stacked layer positioned on the substrate; the semiconductor stack layer includes an island structure and at least one semiconductor light emitting unit, and the trench is located between the semiconductor light emitting unit and the island structure.

In some embodiments, the bottom of the trench is located on a partial thickness of the semiconductor stack.

In some embodiments, the semiconductor island structure does not emit light when the flip-chip light emitting diode is in a powered state.

In some embodiments, the semiconductor stack layer includes a first semiconductor layer, a light emitting layer, and a second semiconductor layer, and the bottom of the trench is lower than the light emitting layer, as viewed in a cross-sectional view in a thickness direction of the flip-chip light emitting diode.

In some embodiments, the bottom of the trench is located on the substrate.

In some embodiments, the semiconductor island structure is located in a central region of the flip-chip light emitting diode.

In some embodiments, the width of the upper surface of the semiconductor island structure is at least 30 μm.

In some embodiments, the upper surface shape of the semiconductor island structure is circular or polygonal.

In some embodiments, the height of the semiconductor island structure is less than or equal to the height of the semiconductor light emitting cell.

In some embodiments, a metal block is also included, the metal block being located over the semiconductor island structure.

In some embodiments, the metal block is in direct contact with an upper surface of the semiconductor island structure.

In some embodiments, the metal block has a thickness of 0.5 to 10 μm.

In some embodiments, a protective layer is further included that covers at least an upper surface and sidewalls of the semiconductor island structures.

In some embodiments, the protective layer is located between the metal block and the semiconductor island structure, or the protective layer is located above the metal block.

In some embodiments, further comprising a first pad and a second pad;

the region covered by the protective layer further comprises the upper surface and the side wall of the semiconductor light-emitting unit; the semiconductor light emitting unit includes a first semiconductor layer, an active layer, and a second semiconductor layer;

the first pad is located on the protective layer and penetrates through the protective layer to be electrically connected with a first semiconductor layer in the semiconductor light-emitting unit, and the second pad is located on the protective layer and penetrates through the protective layer to be electrically connected with a second semiconductor layer in the semiconductor light-emitting unit.

In some embodiments, neither the first pad nor the second pad is over the metal block.

In some embodiments, the number of the semiconductor light emitting units is 1.

In some embodiments, the semiconductor light emitting unit surrounds the periphery of the semiconductor island structure.

In some embodiments, the number of the semiconductor light emitting units is multiple, and the semiconductor light emitting units are arranged at intervals; the number of the semiconductor light emitting units is odd number or even number.

In some embodiments, the semiconductor island structure is located between adjacent semiconductor light emitting cells.

In some embodiments, the semiconductor island structure is located between adjacent semiconductor light emitting cells at a central region of the flip-chip light emitting diode.

In some embodiments, adjacent semiconductor light emitting units are electrically connected.

In some embodiments, the width of the trench between the semiconductor island structure and the semiconductor light emitting cell increases from bottom to top.

The present invention also provides a second flip chip light emitting diode, comprising:

a substrate;

the first and second semiconductor light emitting units are positioned on the substrate and comprise semiconductor stacked layers, and the semiconductor stacked layers comprise a first semiconductor layer, a light emitting layer and a second semiconductor layer;

the groove is positioned between the semiconductor stacked layers of the adjacent first and second semiconductor light-emitting units, and the bottom of the groove is positioned on the substrate;

the semiconductor stack layer of the first semiconductor light emitting unit has a local convex part.

In some embodiments, the semiconductor stack layer of the second semiconductor light emitting unit has a local recess.

In some embodiments, the protrusions and the recesses cause the grooves to extend horizontally in a non-linear manner between adjacent semiconductor light emitting cells.

In some embodiments, the protrusion is located in a central region of the flip-chip light emitting diode.

In some embodiments, the width of the protrusions is at least 30 μm.

In some embodiments, the convex portion and the concave portion are designed to cooperate.

In some embodiments, the edges of the protrusions are non-linear.

In some embodiments, the edge of the protrusion is an arc or a plurality of line segments.

In some embodiments, the thickness of the protrusion is equal to the total thickness of the semiconductor stacked layers.

In some embodiments, an interconnection electrode connecting the first semiconductor light emitting cell and the second semiconductor light emitting cell is further included.

In some embodiments, the interconnect electrode is located over the protrusion.

In some embodiments, the interconnect electrode is not located over the protrusion.

The present application also provides a light emitting device comprising the above-described first or second flip-chip light emitting diode.

Advantageous effects

Compared with the prior art, the application has at least the following beneficial effects:

and a semiconductor stacked layer region acted by the thimble is reserved at the central region of the flip-chip light-emitting diode to form a semiconductor island structure or a convex part, the region where the semiconductor island structure or the convex part is positioned is flat as an action region of the thimble, and when the thimble acts on the region, the risk of puncturing or bursting the protective layer is reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

FIG. 1a is a top view of a flip-chip LED according to an embodiment of the present application;

FIG. 1b is a schematic cross-sectional view A-A of FIG. 1a, according to an embodiment of the present disclosure;

FIG. 2a is a top view of a flip-chip LED according to an embodiment of the present application;

FIG. 2b is a schematic cross-sectional view A-A of FIG. 2a, according to an embodiment of the present application;

FIG. 3 is a schematic cross-sectional view A-A of FIG. 1, according to an embodiment of the present application;

FIG. 4 is a schematic cross-sectional view A-A of FIG. 1, according to an embodiment of the present application;

FIG. 5 is a top view of a flip chip LED according to an embodiment of the present application;

FIG. 6 is a schematic cross-sectional view A-A of FIG. 5, according to an embodiment of the present application;

FIG. 7 is a schematic cross-sectional view A-A of FIG. 5, according to an embodiment of the present application;

FIG. 8 is a schematic cross-sectional view A-A of FIG. 5, according to an embodiment of the present application;

FIG. 9 is a schematic cross-sectional view B-B of FIG. 5, according to an embodiment of the present application;

FIGS. 10-12 are schematic cross-sectional views A-A of a flip-chip LED at different stages of fabrication according to embodiments of the present disclosure;

FIG. 13 is a top view of a flip chip LED according to an embodiment of the present application;

FIG. 14 is a schematic cross-sectional view A-A of FIG. 13, according to an embodiment of the present application.

Illustration of the drawings:

100 a substrate; 200 semiconductor stacked layers; 201 a first semiconductor layer; 202 an active layer; 203 a second semiconductor layer; 210. 210a, 210b semiconductor light emitting units; 210a1 projection; 220 a semiconductor island structure; 230 grooves; 240 grooves; 300 a current blocking layer; 400 a transparent conductive layer; 500 a first electrode; 510 a second electrode; 520 an interconnect electrode; 600 a protective layer; 700 a first pad; 710 a second pad; 800 metal blocks.

Modes for carrying out the invention

The following description of the embodiments of the present application is provided by way of specific examples, and other advantages and effects of the present application will be readily apparent to those skilled in the art from the disclosure herein. The present application is capable of other and different embodiments and its several details are capable of modifications and variations in various respects, all without departing from the spirit of the present application.

In the description of the present application, it should be noted that the terms "upper", "lower", "left" and "right" and the like indicate orientations or positional relationships based on orientations or positional relationships shown in the drawings or orientations or positional relationships conventionally laid out when products of the application are used, and are only used for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation and be operated, and thus, should not be construed as limiting the present application. Furthermore, the terms "first" and "second," etc. are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

Example 1

According to one aspect of the present application, a flip chip light emitting diode is provided. Fig. 1a and 2a are top views of the flip-chip light emitting diode, and fig. 1b, 2b and 3-4 are schematic sectional views a-a of fig. 1a and 2 a.

The flip-chip light emitting diode comprises a substrate and a semiconductor stacking layer positioned on the substrate; the semiconductor stack layer includes an island structure and at least one semiconductor light emitting unit, and the trench is located between the semiconductor light emitting unit and the island structure.

The flip-chip light emitting diode comprises a substrate 100, wherein a semiconductor stacked layer is arranged on the substrate, and the semiconductor stacked layer comprises a first semiconductor layer 201, an active layer 202 and a second semiconductor layer 203. The semiconductor stack layer includes an island structure 220 and a semiconductor light emitting unit 210, the semiconductor light emitting unit 210 surrounds the island structure, and the island structure is located in a central region of the flip chip light emitting diode. A trench 230 is formed between the semiconductor island structure 220 and the semiconductor light emitting unit 210.

The protective layer 600 covers the upper surface and sidewalls of the semiconductor light emitting cell 210, the upper surface and sidewalls of the semiconductor island structure 220, and the trench between the semiconductor island structure 220 and the semiconductor light emitting cell 210.

The front side of the flip-chip light emitting diode is oriented the same as the upper surface of the substrate 100, that is, the central region of the front side of the flip-chip light emitting diode is provided with a semiconductor island structure 220, and the semiconductor island structure 220 is provided independently of the semiconductor light emitting unit 210. The region where the semiconductor island structure 220 is located serves as an action region of the thimble, when the thimble acts on the region, a crack generated by the thimble penetrating or bursting the protection layer 600 is generated on the upper surface of the semiconductor island structure 220 or further extends to the periphery of the side wall of the semiconductor island structure 220, and the groove between the semiconductor light-emitting unit 210 and the semiconductor island structure 220 can block the crack from being transmitted to the protection layer 600 of the light-emitting region to a certain extent, so that the leakage failure phenomenon of the flip-chip light-emitting diode caused by the penetration or bursting of the protection layer 600 at the light-emitting region is avoided, and the reliability of the flip-chip light-emitting diode is improved.

Specifically, the semiconductor light emitting unit 210 is a region for providing light emission, and includes: a first semiconductor layer 201, an active layer 202, and a second semiconductor layer 203. From the top view of fig. 1a, the semiconductor light emitting unit 210 is ring-shaped and disposed around the periphery of the semiconductor island structure 220.

The central region of the flip-chip led where the semiconductor island structure 220 is located is the central region of the top view of the flip-chip led.

As an embodiment, the bottom of trench 230 is located on a partial thickness of the semiconductor stack. As best shown in the cross-sectional view of fig. 1b, the bottom of the trench 230 is lower than the light emitting layer 202, so as to reduce the risk that cracks generated by bursting the passivation layer on the island structure are transferred to the light emitting region to affect the electrical property of the light emitting region. That is, the semiconductor island structure 220 does not emit light when the flip-chip light emitting diode is energized. The bottom of the trench 230 is located on the first semiconductor layer 201, and the island structure on the first semiconductor layer 201 may include a partial thickness of the first semiconductor layer 201, the light emitting layer 202, and the second semiconductor stacked layer 203. That is, the semiconductor island structures are not provided on the substrate independently of the semiconductor light emitting cells 210, but are connected together through the first semiconductor layer 201.

As a more preferred embodiment, as shown in fig. 2a-2b, the semiconductor island structure 220 is disposed in the central region of the flip-chip light emitting diode, the semiconductor island structure 220 and the semiconductor light emitting unit 210 are independently located on the substrate 100, and there is a trench 230 between them, with no semiconductor layer or conductive layer connecting them. The bottom of the trench is located on the substrate 100. Therefore, the grooves are deeper, the semiconductor island structures and the semiconductor light emitting units are independent from each other, the risk of leakage failure of the flip-chip light emitting diode due to the fact that the protective layer 600 is punctured or burst is lower, and the reliability of the flip-chip light emitting diode can be further improved.

In the embodiment of fig. 2b, the material composition of the stacked material layers of the semiconductor island structure 220 and the thickness of each layer are the same as those of the semiconductor light emitting unit 210. The thickness of the semiconductor light emitting unit 210 is 3 to 10 μm.

Referring to fig. 2 to 4, the semiconductor light emitting unit 210 includes a first semiconductor stack layer, and the semiconductor island structure 220 includes a second semiconductor stack layer. The height of the semiconductor island structure 220 is equal to or less than the height of the semiconductor light emitting unit 210, and the height of the semiconductor island structure 220 is preferably equal to or less than the height of the first semiconductor stack layer. Each of the first and second semiconductor stacked layers includes a first semiconductor layer 201, an active layer 202, and a second semiconductor layer 203.

In order to obtain the semiconductor light emitting unit 210 and the semiconductor island structure 220, the semiconductor stack layer 200 may be obtained on the substrate 100, and then the semiconductor stack layer 200 may be etched from the surface of the semiconductor stack layer 200 to the surface of the substrate 100 through a vertical etching process to form the independent semiconductor light emitting unit 210 and the semiconductor island structure 220. Preferably, a portion of the semiconductor material layer on the semiconductor island structure 220 is further etched, so that the height of the semiconductor island structure 220 is smaller than the height of the semiconductor light emitting unit 210.

The shape of the upper surface of the semiconductor island structure 220 includes, but is not limited to, a circle or a polygon, and the width of the upper surface of the semiconductor island structure 220 is at least 30 μm, preferably, the width of the upper surface of the semiconductor island structure 220 is implemented according to the current thimble size, and the width of the upper surface of the semiconductor island structure 220 is at least 50 μm and at most 80 μm. In this embodiment, the upper surface and the lower surface of the semiconductor island structure 220 are both circular, and the diameter of the upper surface of the semiconductor island structure 220 is smaller than the diameter of the lower surface of the semiconductor island structure 220.

Preferably, the width of the trench between the semiconductor island structure 220 and the semiconductor light emitting unit 210W ₁And the number of the holes is increased from bottom to top. Width of trench at bottomW ₁Is greater than or equal to 3 mu m.

In the semiconductor stack layer, the first semiconductor layer 201 is an N-type semiconductor layer, the active layer 202 is a multi-layer quantum well layer, which can provide blue, green or red radiation, and can also provide ultraviolet or infrared radiation, and the second semiconductor layer 203 is a P-type semiconductor layer. The N-type semiconductor layer, the multiple quantum well layers and the P-type semiconductor layer are only basic constituent units of the first semiconductor stacked layer, and on the basis, the first semiconductor stacked layer can also comprise other functional structure layers with an optimization effect on the performance of the flip-chip light emitting diode, such as an undoped semiconductor layer. The thickness of the semiconductor stacked layer is 3 to 15 μm.

The first pad 700 and the second pad 710 are both located on the protective layer 600, and are both electrically connected to the semiconductor light emitting unit 210 through the protective layer 600.

When the flip-chip light emitting diode is mounted on the application substrate, the first and

second pads

700 and 710 may be connected to electrodes on the application substrate through a reflow process or a thermal compression process. A connection layer containing a tin component may be present between the first pad 700, the second pad 710 and the electrode on the application substrate, and the tin-containing connection layer may be a tin paste. A tin-containing connection layer may be disposed on the first pad 700 or the second pad 710, thereby avoiding the use of a tin paste.

The first and

second pads

700 and 710 may include an adhesion layer, a reflection layer, a barrier layer, and a gold layer. Wherein the adhesion layer is a titanium layer or a chromium layer; the reflecting layer is an aluminum layer; the barrier layer is a nickel layer, or a repeated lamination of a nickel layer and a platinum layer. The barrier layer can be used for preventing the tin-containing connecting layer from penetrating into the flip-chip light-emitting diode. Preferably, the first and

second pads

700 and 710 further include a thick tin layer on the gold layer.

From the top view of the flip-chip light emitting diode shown in fig. 1a, 2a, the semiconductor island structure 220 is located between the first pad 700 and the second pad 710. As seen from the a-a cross-sectional views of the flip-chip light emitting diode shown in fig. 1b and 2b, neither the first bonding pad 700 nor the second bonding pad 710 is located above the semiconductor island structure 220.

In one embodiment, the flip-chip light emitting diode may further include a metal block 800, and the metal block 800 is located above the semiconductor island structure 220. The metal block 800 has a certain ductility, and can buffer the acting force of the thimble to a certain extent. Preferably, the thickness of the metal block 800 is 0.5-10 μm, and the thickness of the metal block 800 is preferably 1-3 μm, in this embodiment, the material of the metal block 800 includes, but is not limited to, Au, Ti, Al, Cr, Pt, TiW alloy, or any combination of Ni.

Referring to fig. 3, a metal block 800 is in direct contact with the upper surface of the semiconductor island structure 220, and a protective layer 600 is located above the metal block 800. Specifically, the metal block 800 covers the upper surface of the semiconductor island structure 220, or the metal block 800 covers the upper surface and at least a portion of the sidewalls of the semiconductor island structure 220.

Alternatively, referring to fig. 4, the metal block 800 is located on the upper surface of the protection layer 600 and above the semiconductor island structure 220, that is, the protection layer 600 is located between the metal block 800 and the semiconductor island structure 220. Preferably, the metal block 800 has the same material and thickness as the first pad 700 and the second pad 710, and the metal block 800 is located between the first pad 700 and the second pad 710 and keeps a certain distance from the first pad 700 and the second pad 710. The width of the metal block 800 is less than or equal to the width of the semiconductor island structure 220.

It should be noted that the semiconductor island structure 220 is designed to prevent the protective layer 600 at the semiconductor light emitting unit 210 from being broken to some extent, and the metal block 800 is not necessarily provided.

In one embodiment, the substrate 100 is a transparent substrate, for example, a sapphire substrate. The upper surface of the substrate 100 may be provided with a sapphire pattern, or the upper surface of the substrate 100 may be provided with a pattern of a heterogeneous material, such as silicon oxide. The height of the pattern may be 1 to 3 μm, and the width may be 1 to 4. The substrate 100 further includes an upper surface, a lower surface, and a side surface, and light radiated from the active layer 202 may radiate light from the side surface and the upper surface of the substrate 100. The thickness of the substrate 100 is preferably 60 μm or more, for example, 80 μm, 120 μm, 150 μm, or 250 μm.

In one embodiment, referring to fig. 1 to 4, the first semiconductor stack layer has a mesa exposing a portion of the first semiconductor layer 201, and the first electrode 500 is formed on the mesa.

The semiconductor light emitting unit 210 further includes a transparent conductive layer 400, including but not limited to an ito layer, on the second semiconductor layer 203. The transparent conductive layer 400 includes an opening, and the opening exposes a portion of the second semiconductor layer 203. The second electrode 510 is formed on the transparent conductive layer 400 and contacts the second semiconductor layer 203 through the opening.

The second electrode 510 includes a block portion and at least one strip portion extending from the block portion, and a portion of the second electrode 510 including the block portion or the strip portion contacts the second semiconductor layer 203 through the opening in the transparent conductive layer 400 to improve adhesion of the second electrode 510.

The width of the opening located under the stripe portion in the second electrode 510 is greater than the width of the stripe portion in the second electrode 510. The width of the opening under the block portion in the second electrode 510 is smaller than the width of the block portion in the second electrode 510 to achieve that the edge of the block portion is located on the upper surface of the transparent conductive layer 400.

The first electrode 500 and the second electrode 510 may include an adhesion layer, a reflective layer and a barrier layer, wherein the adhesion layer is a chromium layer or a titanium layer, the reflective layer is an aluminum layer, and the barrier layer is a repeated lamination of a titanium layer and a platinum layer.

The passivation layer 600 is provided with through holes respectively located above the first electrode 500 and the second electrode 510, and the first pad 700 and the second pad 710 are located on the passivation layer 600 and connected to the first electrode 500 and the second electrode 510 through the through holes respectively. Neither the first pad 700 nor the second pad 710 is above the metal block 800.

The protection layer 600 includes, but is not limited to, a distributed bragg reflector or a single-layer insulating layer, and in this embodiment, the material of the protection layer 600 is SiO₂、TiO₂、ZnO₂、ZrO₂、Cu₂O₃And at least two of the different materials, in particular, a distributed bragg reflector made by alternately laminating two materials in a multilayer using a technique such as electron beam evaporation or ion beam sputtering.

Example 2

The high voltage flip-chip light emitting diode is a modified design of a conventional flip-chip light emitting diode, and is divided into a plurality of sub-semiconductor light emitting units with equal areas through a trench, and then the sub-semiconductor light emitting units are electrically connected in series/parallel with each other. The design leads to the central area of the even number of the sub-semiconductor light-emitting units to have a groove, because the flip light-emitting diode needs to use the thimble to act on the middle area of one side of the front electrode of the light-emitting diode when in transfer, when the groove is positioned in the central area, the insulating layer is easily cracked by the thimble due to uneven surface, so that water vapor is easy to intrude into the self-light-emitting units along the cracked position, and the light-emitting diode is easy to lose efficacy in the aging test or long-term use process.

The invention designs the high-voltage flip-chip light-emitting diode with the anti-thimble structure aiming at the problem, and can effectively solve the abnormity.

The embodiment provides a high-voltage flip-chip light emitting diode. Fig. 5 is a top view of the flip-chip light emitting diode, fig. 6 to 8 are schematic sectional views a-a of fig. 5, and fig. 9 is a schematic sectional view B-B of fig. 5.

The flip chip light emitting diode includes a substrate 100, a plurality of semiconductor light emitting cells 210 formed on the substrate 100, and a semiconductor island structure 220. The plurality of semiconductor light emitting units 210 are arranged in a predetermined direction and spaced apart from each other, and adjacent semiconductor light emitting units 210 are electrically connected to each other. The semiconductor island structure 220 is located between adjacent semiconductor light emitting cells 210 at a central region of the flip chip light emitting diode, which is referred to herein as a central region of a top view thereof, and a trench is present between the semiconductor light emitting cells 210 adjacent thereto. The number of the semiconductor light emitting units 210 is an odd number or an even number, and the number of the semiconductor light emitting units 210 is preferably an even number.

The protective layer 600 covers the upper surface and sidewalls of each of the semiconductor light emitting cells 210, the upper surface and sidewalls of the semiconductor island structure 220, and the trench between the semiconductor island structure 220 and the semiconductor light emitting cells 210.

The first bonding pad 700 is disposed on the protection layer 600 and electrically connected to the leading semiconductor light emitting unit 210 through the protection layer 600, and the second bonding pad 710 is disposed on the protection layer 600 and electrically connected to the trailing semiconductor light emitting unit 210 through the protection layer 600.

Preferably, the width of the trench between the semiconductor island structure 220 and the semiconductor light emitting cell 210 adjacent theretoW ₁And the number of the holes is increased from bottom to top. Width of trench at bottomW ₁Is greater than or equal to 3 μm and less than or equal to 15 μm.

In one embodiment, the material composition of the stacked material layers of the semiconductor island structure 220 and the thickness of each layer are the same as the semiconductor light emitting unit 210. The thickness of the semiconductor light emitting unit 210 is 3 to 10 μm.

Referring to fig. 6 to 8, each of the semiconductor light emitting cells 210 includes a first semiconductor stack layer, and the semiconductor island structure 220 includes a second semiconductor stack layer. The height of the semiconductor island structure 220 is equal to or less than the height of the semiconductor light emitting unit 210, and the height of the semiconductor island structure 220 is preferably equal to or less than the height of the first semiconductor stack layer. Each of the first semiconductor stacked layer and the second semiconductor stacked layer includes a first semiconductor layer 201, an active layer 202, and a second semiconductor layer 203; the first semiconductor layer 201 is an N-type semiconductor layer, the active layer 202 is a multi-layer quantum well layer that can provide blue, green, or red radiation, and can also provide ultraviolet or infrared radiation, and the second semiconductor layer 203 is a P-type semiconductor layer. The N-type semiconductor layer, the multi-layer quantum well layer and the P-type semiconductor layer are only basic constituent units of the first semiconductor stacked layer, and on the basis, the first semiconductor stacked layer can further comprise other functional structure layers with an optimization effect on the performance of the flip-chip light-emitting diode.

In order to obtain a plurality of semiconductor light emitting cells 210 and semiconductor island structures 220, the semiconductor stack layer 200 may be obtained on the substrate 100, and then the semiconductor stack layer 200 may be etched from the surface of the semiconductor stack layer 200 to the surface of the substrate 100 through a vertical etching process to form a plurality of semiconductor light emitting cells 210 and semiconductor island structures 220. Preferably, a portion of the semiconductor material layer on the semiconductor island structure 220 is further etched, so that the height of the semiconductor island structure 220 is smaller than the height of the semiconductor light emitting unit 210.

The shape of the upper surface of the semiconductor island structure 220 includes, but is not limited to, a circle or a polygon, and the width of the upper surface of the semiconductor island structure 220 is at least 30 μm, preferably, the width of the upper surface of the semiconductor island structure 220 is implemented according to the current thimble size, and the width of the upper surface of the semiconductor island structure 220 is at least 40 μm or at least 50 μm, and at most 80 μm. In this embodiment, the upper surface and the lower surface of the semiconductor island structure 220 are both circular, and the diameter of the upper surface of the semiconductor island structure 220 is smaller than the diameter of the lower surface of the semiconductor island structure 220.

In one embodiment, the flip-chip light emitting diode may further include a metal block 800, and the metal block 800 is located above the semiconductor island structure 220. The metal block 800 has a certain ductility, and can buffer the acting force of the thimble to a certain extent. The thickness of the metal block 800 is 0.5-10 μm, and the thickness of the metal block 800 is preferably 1-3 μm, in this embodiment, the material for preparing the metal block 800 includes, but is not limited to, Au, Ti, Al, Cr, Pt, TiW alloy or any combination of Ni.

Referring to fig. 7, a metal block 800 is in direct contact with the upper surface of the semiconductor island structure 220, and a protective layer 600 is located above the metal block 800. Specifically, the metal block 800 covers the upper surface of the semiconductor island structure 220, or the metal block 800 covers the upper surface and at least a portion of the sidewalls of the semiconductor island structure 220.

Alternatively, referring to fig. 8, the metal block 800 is located on the upper surface of the protection layer 600 and above the semiconductor island structure 220, that is, the protection layer 600 is located between the metal block 800 and the semiconductor island structure 220. Preferably, the metal block 800 has the same material and thickness as the first pad 700 and the second pad 710, and the metal block 800 is located between the first pad 700 and the second pad 710 and keeps a certain distance from the first pad 700 and the second pad 710. The width of the metal block 800 is less than or equal to the width of the semiconductor island structure 220.

In one embodiment, referring to fig. 9, the flip-chip light emitting diode further includes a current blocking layer 300, and in each adjacent two semiconductor light emitting cells 210, the current blocking layer 300 extends from the second semiconductor layer 203 in the left semiconductor light emitting cell 210 to the first semiconductor layer 201 in the right semiconductor light emitting cell 210. The material of the current blocking layer 300 may be selected from one or more of silicon oxide, silicon nitride, silicon carbide, or silicon oxynitride.

The first electrode 500 is disposed on the first semiconductor light emitting unit 210, and the first electrode 500 is electrically connected to the first semiconductor layer 201 in the first semiconductor light emitting unit 210.

The semiconductor light emitting unit 210 of the tail end is provided with a second electrode 510. In the semiconductor light emitting unit 210 at the tail end. A transparent conductive layer 400 is formed on the second semiconductor layer 203, and the transparent conductive layer 400 includes, but is not limited to, an ito layer. The transparent conductive layer 400 includes an opening exposing a portion of the second semiconductor layer 203, and the second electrode 510 contacts the second semiconductor layer 203 through the opening.

The two adjacent semiconductor light emitting units 210 are electrically connected through an interconnection electrode 520, specifically, in each two adjacent semiconductor light emitting units 210, the first semiconductor light emitting unit 210a includes the transparent conductive layer 400, the transparent conductive layer 400 is located on the current blocking layer 300 above the second semiconductor layer 203, and the interconnection electrode 520 extends from the transparent conductive layer 400 in the left semiconductor light emitting unit 210 to the first semiconductor layer 201 in the right semiconductor light emitting unit 210.

The first electrode 500, the second electrode 510, and the interconnection electrode 520 may include an adhesion layer, a reflective layer, and a barrier layer, wherein the adhesion layer is a chromium layer or a titanium layer, the reflective layer is an aluminum layer, and the barrier layer is a repeated stack of a titanium layer and a platinum layer.

The passivation layer 600 is provided with through holes respectively located above the first electrode 500 and the second electrode 510, and the first pad 700 and the second pad 710 are located on the passivation layer 600 and connected to the first electrode 500 and the second electrode 510 through the through holes respectively.

The design can be applied to lighting devices, displays and the like, and is better suitable for light emitting diodes designed to be small in size, and has low requirements on brightness but high requirements on reliability, and corresponding lighting devices such as televisions for backlight applications, display screens or RGB three-color-based light emitting diode display screens.

Taking backlight application as an example, a direct type backlight design is generally adopted, and area dimming in a smaller range is realized through densely arranging and inversely arranging light emitting diodes in a large batch. However, the use of flip-chip leds in large quantities requires higher transfer yields and performance stability. By adopting the island design, the problems can be effectively relieved, the transfer yield in large batch can be improved, and the performance stability of the light-emitting diode can be ensured.

Example 3

The application provides a preparation method of a flip-chip light-emitting diode, and particularly provides a preparation method of the flip-chip light-emitting diode shown in figure 1. The preparation method comprises the following steps:

s1, referring to fig. 10, a substrate 100 is provided, and a semiconductor stack layer 200 is formed on the substrate 100.

The semiconductor stacked layer 200 includes a first semiconductor layer 201, an active layer 202, and a second semiconductor layer 203; the first semiconductor layer 201 is an N-type semiconductor layer, the active layer 202 is a multi-layer quantum well layer, and the second semiconductor layer 203 is a P-type semiconductor layer. In this embodiment, the substrate 100 is a sapphire patterned substrate or a sapphire flat-bottom substrate.

S2, referring to fig. 11, the semiconductor stack layer 200 is etched and a trench 230 penetrating the semiconductor stack layer 200 is formed, the trench 230 is ring-shaped and divides the semiconductor stack layer 200 into an independent semiconductor light emitting unit 210 and a semiconductor island structure 220, and the semiconductor light emitting unit 210 surrounds the periphery of the semiconductor island structure 220.

The width of the trench 230 is the width of the trench between the semiconductor island structure 220 and the semiconductor light emitting unit 210W ₁，W ₁And the number of the holes is increased from bottom to top.

The upper surface of the semiconductor island structure 220 is circular or polygonal in shape, and the width of the upper surface of the semiconductor island structure 220 is at least 30 μm, preferably, the width of the upper surface of the semiconductor island structure 220 is implemented according to the current thimble size, and the width of the upper surface of the semiconductor island structure 220 is at least 40 μm or at least 50 μm. In this embodiment, the upper surface and the lower surface of the semiconductor island structure 220 are both circular, and the diameter of the upper surface of the semiconductor island structure 220 is smaller than the diameter of the lower surface of the semiconductor island structure 220.

S3, referring to fig. 12, a protection layer 600 is formed at the semiconductor light emitting unit 210, the semiconductor island structure 220 and the trench 230, wherein the protection layer 600 includes, but is not limited to, a dbr or a single insulating layer.

Specifically, the semiconductor light emitting unit 210 includes a first semiconductor stack layer on which a transparent conductive layer 400 is formed, the transparent conductive layer 400 includes an opening, and the opening exposes a portion of the second semiconductor layer 203. The material of the transparent conductive layer 400 is generally selected to be a conductive material having a transparent property, and may be specifically selected to be indium tin oxide.

The first semiconductor stack layer has a mesa exposing a portion of the first semiconductor layer 201, and the first electrode 500 is formed on the mesa; a second electrode 510 is formed on the transparent conductive layer 400, and the second electrode 510 contacts the second semiconductor layer 203 through the opening.

The protective layer 600 is etched and via holes are formed over the first electrode 500 and the second electrode 510, respectively, for forming a first pad 700 corresponding to the first electrode 500 and a second pad 710 corresponding to the second electrode 510.

S4, forming a first pad 700 and a second pad 710 electrically connected to the semiconductor light emitting unit 210. This step results in the flip-chip led shown in fig. 2.

In one embodiment, the method further comprises: forming a metal block 800 on the semiconductor island structure 220 while forming the first electrode 500 and the second electrode 510; the metal block 800 covers the upper surface of the semiconductor island structure 220, or the metal block 800 covers the upper surface and at least a portion of the sidewalls of the semiconductor island structure 220. The thickness of the metal block 800 is 0.5-10 μm, and the thickness of the metal block 800 is preferably 1-3 μm, and in this embodiment, the material of the metal block 800 may be the same as the first electrode 500 and the second electrode 510. This step results in the flip-chip led shown in fig. 3.

In one embodiment, the method further comprises: the metal bump 800 is formed on a region above the semiconductor island structure 220 in the upper surface of the protection layer 600 at the same time as the first pad 700 and the second pad 710 are formed. The thickness of the metal block 800 is 0.5-10 μm, and the thickness of the metal block 800 is preferably 1-3 μm, and in this embodiment, the metal block 800 may be made of the same material as the first pad 700 and the second pad 710. This step results in the flip-chip led shown in fig. 4.

Example 4

The application provides a preparation method of a flip-chip diode, and particularly provides a preparation method of a flip-chip light-emitting diode shown in fig. 5. The preparation method comprises the following steps:

s10, providing a substrate 100, and forming a plurality of semiconductor light emitting units 210 arranged in a predetermined direction and spaced apart from each other on the substrate 100, wherein adjacent semiconductor light emitting units 210 are electrically connected to each other; a semiconductor island structure 220 is formed between the adjacent semiconductor light emitting cells 210 at the central region of the flip chip light emitting diode, and a trench is formed between the semiconductor island structure 220 and the semiconductor light emitting cell 210 adjacent thereto. The number of the semiconductor light emitting units 210 is an odd number or an even number, and the number of the semiconductor light emitting units 210 is preferably an even number. The semiconductor island structure 220 is located in the central region of the flip-chip light emitting diode so as to achieve the area of the light emitting region of each semiconductor light emitting unit 210 as close as possible.

Specifically, a semiconductor stack layer 200 is formed on a substrate 100, the semiconductor stack layer 200 including a first semiconductor layer 201, an active layer 202, and a second semiconductor layer 203; the first semiconductor layer 201 is an N-type semiconductor layer, the active layer 202 is a multi-layer quantum well layer, and the second semiconductor layer 203 is a P-type semiconductor layer. The semiconductor stack layer 200 is etched and a plurality of first semiconductor stack layers for forming the semiconductor light emitting unit 210 are formed, adjacent first semiconductor stack layers are spaced apart by a trench 240, and the semiconductor island structure 220 is formed in the trench 240 in the central region of the substrate 100.

The width of the trench between the semiconductor island structure 220 and the semiconductor light emitting cell 210 adjacent theretoW ₁And the number of the holes is increased from bottom to top. The upper surface of the semiconductor island structure 220 is circular or polygonal in shape, and the width of the upper surface of the semiconductor island structure 220 is at least 30 μm, preferably, the width of the upper surface of the semiconductor island structure 220 is implemented according to the current thimble size, and the width of the upper surface of the semiconductor island structure 220 is at least 50 μm. In this embodiment, the upper surface and the lower surface of the semiconductor island structure 220 are both circular, and the diameter of the upper surface of the semiconductor island structure 220 is smaller than the diameter of the lower surface of the semiconductor island structure 220.

In each adjacent two of the semiconductor light emitting cells 210, the current blocking layer 300 extends from the left second semiconductor layer 203 to the right first semiconductor layer 201 through the trench 240. The material of the current blocking layer 300 may be selected from one or more of silicon oxide, silicon nitride, silicon carbide, or silicon oxynitride.

In the semiconductor light emitting unit 210 at the tail end, a transparent conductive layer 400 is formed on the second semiconductor layer 203, and a material thereof is generally selected to be a conductive material having a transparent property, and may be specifically selected to be indium tin oxide. In each adjacent two of the semiconductor light emitting cells 210, the left semiconductor light emitting cell 210 also includes the transparent conductive layer 400, and the transparent conductive layer 400 is located on the current blocking layer 300 above the second semiconductor layer 203.

A first electrode 500 is formed on the first semiconductor layer 201 in the head-end semiconductor light emitting unit 210.

A second electrode 510 is formed on the transparent conductive layer 400 in the semiconductor light emitting unit 210 at the tail end, and the second electrode 510 contacts the second semiconductor layer 203 through the opening.

An interconnection electrode 520 for connecting adjacent semiconductor light emitting cells 210 is formed, and in every adjacent two semiconductor light emitting cells 210, the interconnection electrode 520 extends from the transparent conductive layer 400 in the left semiconductor light emitting cell 210 to the first semiconductor layer 201 in the right semiconductor light emitting cell 210.

S20, forming a protection layer 600 at the plurality of semiconductor light emitting cells 210, the semiconductor island structure 220 and the trench 240, wherein the protection layer 600 includes, but is not limited to, a distributed bragg reflector or a single-layer insulation layer.

S30, a first bonding pad 700 electrically connected to the head-end semiconductor light emitting unit 210 and a second bonding pad 710 electrically connected to the tail-end semiconductor light emitting unit 210 are formed. This step results in the flip-chip led shown in fig. 6.

In one embodiment, the method further comprises: forming a metal block 800 on the semiconductor island structure 220 while forming the first electrode 500, the second electrode 510, and the interconnection electrode 520; the metal block 800 covers the upper surface of the semiconductor island structure 220, or the metal block 800 covers the upper surface and at least a portion of the sidewalls of the semiconductor island structure 220. The thickness of the metal block 800 is 0.5-10 μm, and the thickness of the metal block 800 is preferably 1-3 μm, and in this embodiment, the metal block 800 may be made of the same material as the first electrode 500, the second electrode 510, or the interconnection electrode 520. This step results in the flip-chip led shown in fig. 7.

According to an aspect of the present application, there is provided a light emitting device, which may be a lighting device, a backlight device, a display device, such as a luminaire, a television, a mobile phone, a panel, or may be an RGB display screen. The light emitting device includes the flip light emitting diode in the above embodiment, and the flip light emitting diode is integrally mounted on the application substrate or the package substrate in a number of hundreds or thousands or tens of thousands to form a light emitting source portion.

According to the above technical solutions, the semiconductor island structure 220 is formed at the central region of the flip-chip light emitting diode, and a trench is formed between the semiconductor island structure 220 and the semiconductor light emitting unit 210, and is not used in the conductive light emitting process of the flip-chip light emitting diode; the region where the semiconductor island structure 220 is located serves as an action region of the thimble, and when the thimble acts on the region, the crack of the protection layer 600 punctured or pierced by the thimble only extends to the periphery of the upper surface or the side wall of the semiconductor island structure 220, so that the crack can be prevented from being directly transmitted to the protection layer 600 at the semiconductor light-emitting unit 210 to a certain extent, thereby preventing the occurrence of leakage failure phenomenon of the flip-chip light-emitting diode due to the fact that the protection layer 600 at the semiconductor light-emitting unit 210 is punctured or pierced, and improving the reliability of the flip-chip light-emitting diode.

Example 5

According to a second aspect of the present invention, as a modification of embodiment 2, this embodiment provides a high-voltage flip-chip light emitting diode. Fig. 13 is a top view of the flip chip light emitting diode, and fig. 14 is a schematic sectional view taken along line a-a of fig. 13.

The flip chip light emitting diode includes a substrate 100, at least two semiconductor light emitting cells formed on the substrate 100. The plurality of semiconductor light emitting units are arranged in a preset direction at intervals, and adjacent semiconductor light emitting units are electrically connected. As shown, first and second semiconductor

light emitting units

210a and 210b are included. The first and second semiconductor

light emitting units

210a, 210b are located on the substrate 100 and are semiconductor stacked layers, and the semiconductor stacked layers include a first semiconductor layer 201, a light emitting layer 202 and a second semiconductor layer 203; the first and second semiconductor

light emitting cells

210a and 210b have a trench 230 therebetween, and the bottom of the trench 230 is located on the substrate 100.

The semiconductor stack layer of the first semiconductor light emitting cell 210a has a local protrusion 210a1, and the semiconductor stack layer of the second semiconductor light emitting cell 210b has a local recess.

The protrusion 210a1 is located on one edge of the semiconductor stack layer of the first semiconductor light emitting cell 210a, and the width of the semiconductor stack layer of the first semiconductor light emitting cell 210a is measured along a direction extending parallel to one side of the flip chip light emitting diode, and the protrusion 210a1 widens the width of the entire semiconductor stack layer of the first semiconductor light emitting cell 210 a.

The protrusion 210a1 is located in the center region of the flip chip led, where the center region of the flip chip led is the center region of the top view of the led in a plan view or a horizontal position.

The protective layer 600 covers the upper and sidewalls of each semiconductor light emitting cell, the upper and sidewalls including the protrusion 210a1, and the trench 230 between the protrusion 210a1 and the adjacent semiconductor light emitting cell.

When the ejector pins of the transfer device are applied to the flip-chip leds supported by a flexible material such as a blue film to transfer the flip-chip leds to another device or a substrate, for example, an application substrate, the ejector pins are applied to the protection layer 600 of the protrusions 210a1 between the first pads 700 and the second pads 710. Compared with the risk of electric leakage failure caused by the fact that the grooves between the semiconductor light emitting units 210 serve as active areas of the flip-chip light emitting diode and the protective layer 600 is punctured or burst, the flat surface provided by the convex portions can reduce the risk of cracks caused by puncturing or bursting the protective layer 600 by an ejector pin, and the reliability of the flip-chip light emitting diode is improved.

In addition, although the projection design has a higher risk of insulating layer cracking than the design of embodiment 2, the projection 210a1 can emit light when energized, and the projection 210a1 has a reduced loss of light efficiency. Furthermore, the interconnection electrode can also be designed to avoid the convex part 210a1, and the width of the interconnection electrode can be narrower, so that the influence of light absorption is reduced.

The number of the semiconductor light emitting cells 210 is an odd number or an even number, the number of the semiconductor light emitting cells 210 is preferably an even number, and the semiconductor light emitting cells are arranged along one straight direction.

The thickness of the protrusion 210a1 of the first semiconductor light emitting cell 210a is equal to the maximum thickness of the semiconductor stacked layer of the semiconductor light emitting cell 210a, the bottom of the protrusion 210a1 is the bottom of the semiconductor stacked layer, and the top of the protrusion 210a1 is the top of the semiconductor stacked layer (i.e., the second semiconductor layer).

The semiconductor stack layer comprises a first semiconductor layer 201, an active layer 202 and a second semiconductor layer 203; the first semiconductor layer 201 is an N-type semiconductor layer, the active layer 202 is a multi-layer quantum well layer that can provide blue, green, or red radiation, and can also provide ultraviolet or infrared radiation, and the second semiconductor layer 203 is a P-type semiconductor layer. The N-type semiconductor layer, the multi-layer quantum well layer and the P-type semiconductor layer are only basic constituent units required by the semiconductor stacked layer for light emitting, and on the basis, the semiconductor stacked layer can also comprise other functional structure layers with an optimization effect on the performance of the flip-chip light emitting diode.

The semiconductor light emitting unit 210 has a thickness of 3 to 10 μm.

The protrusion 210a1 is located on the edge of the first semiconductor light emitting cell 210a, and the width of the upper surface of the protrusion 210a1 (i.e., the upper surface of the second semiconductor layer) is at least 30 μm. That is, in order to design the convex portion of the first semiconductor light emitting unit, the width of the first semiconductor light emitting unit is widened by at least 30 μm (measured in a direction parallel to one side of the flip-chip light emitting diode) with respect to the width at other positions. Preferably, the width of the upper surface of protrusion 210a1 is implemented according to current thimble size, and the width of the upper surface of semiconductor island structure 220 is at least 50 μm and at most 100 μm.

Since the convex part enables the edge of the first semiconductor light emitting unit to be horizontally widened towards the second semiconductor light emitting unit, the edge of the semiconductor stacked layer of the adjacent second semiconductor light emitting unit is concave inwards. The edge of the second semiconductor light-emitting unit is matched with the concave part and the convex part.

The recess locally narrows the overall width of the semiconductor light emitting stack of the second semiconductor light emitting unit.

Preferably, when viewed from the top of fig. 13, the edge of the protrusion 210a1 is nonlinear, and the edge of the recess is nonlinear. For example, the edge of the convex part is an arc or a plurality of line segments connected.

The second semiconductor light emitting unit 210b is provided with a first electrode 500, and the first electrode 500 is electrically connected to the first semiconductor layer 201 in the semiconductor light emitting unit 210.

The first semiconductor light emitting cell 210a is provided with a second electrode 510. In each semiconductor light emitting unit, a transparent conductive layer 400 is formed on the second semiconductor layer 203, and the transparent conductive layer 400 includes, but is not limited to, an ito layer. The second electrode 510 is located under the transparent conductive layer 400, and a current blocking layer 300 may be located under the transparent conductive layer 400. The current blocking layer 300 is simultaneously positioned under the second electrode 510 to block the vertical transmission of current and to facilitate the current spreading.

As an alternative embodiment, the transparent conductive layer 400 may include an opening exposing a portion of the second semiconductor layer 2, and the second electrode contacts the second semiconductor layer through the opening. The second electrode 510 includes a block portion (wider than the strip portion) and at least one strip portion extending from the block portion, and the second electrode 510 includes a portion of the block or a portion of the strip in contact with the second semiconductor layer 203 through the opening in the transparent conductive layer 400 to improve the adhesion of the second electrode 510.

The two adjacent semiconductor light emitting units 210 are electrically connected through an interconnection electrode 520, specifically, in each two adjacent semiconductor light emitting units 210, the first semiconductor light emitting unit 210a includes the transparent conductive layer 400, the transparent conductive layer 400 is located on the current blocking layer 300 above the second semiconductor layer 203, and the interconnection electrode 520 extends from the transparent conductive layer 400 in the first semiconductor light emitting unit 210a across the trench to the first semiconductor layer 201 in the second semiconductor light emitting unit 210 b. The current blocking layer 300 is interposed between the interconnection electrode 520 and the sidewalls of the first semiconductor light emitting cell 210a, the sidewalls of the second semiconductor light emitting cell 210b and the bottom of the trench in the trench.

As an embodiment, the transparent electrode layer 400 extends to the upper surface of the protrusion 210a1, and the interconnection electrode 520 is located on the transparent electrode layer 400 above the upper surface of the protrusion 210a1 and extends to the first semiconductor layer of the second semiconductor light emitting unit 210b, in order to achieve the flat region for the function of the lift-off pin, the width of the interconnection electrode 520 is at least 30 μm, and the interconnection electrode 520 is a metal structure, which can play a certain role in buffering the function of the lift-off pin.

As a more preferable embodiment, as shown in fig. 13 to 14, the transparent electrode layer 400 extends to the upper surface of the protrusion, the interconnection electrode 520 is not located above the protrusion 210a1, the interconnection electrode 520 is designed to avoid the protrusion 210a1, for example, the interconnection electrode 520 is located on one side or two sides of the protrusion 210a1, so that the interconnection electrode can be made narrower and the light absorption can be reduced.

The first pad 700 is disposed on the protective layer 600 and electrically connected to one of the semiconductor light emitting units (e.g., the first semiconductor light emitting unit 210 a) through the protective layer 600, and the second pad 710 is disposed on the protective layer 600 and electrically connected to the other semiconductor light emitting unit (e.g., the second semiconductor light emitting unit 210b) through the protective layer 600.

Preferably, the width of the trench at the bottomW ₁Is greater than or equal to 3 mu m.

The first electrode 500, the second electrode 510, and the interconnection electrode 520 are metal electrodes and may include an adhesion layer, a reflective layer, and a barrier layer, wherein the adhesion layer is a chromium layer or a titanium layer, the reflective layer is an aluminum layer, and the barrier layer is a repeated stack of a titanium layer and a platinum layer.

The foregoing is only a preferred embodiment of the present application, and it should be noted that, for those skilled in the art, several modifications and substitutions can be made without departing from the technical principle of the present application, and these modifications and substitutions should also be regarded as the protection scope of the present application.

Claims

1. The flip-chip light-emitting diode is characterized by comprising a substrate and a semiconductor stacked layer positioned on the substrate, wherein the semiconductor stacked layer comprises at least one semiconductor light-emitting unit and an island structure, and a groove is positioned between the semiconductor light-emitting unit and the island structure.

2. The flip-chip led of claim 1, wherein the bottom of the trench is located over a portion of the thickness of the semiconductor stack.

3. The flip-chip light emitting diode of claim 1, wherein: when the flip-chip light emitting diode is in a power-on state, the semiconductor island structure does not emit light.

4. The flip chip light emitting diode of claim 1, wherein the semiconductor stack layer comprises a first semiconductor layer, a light emitting layer and a second semiconductor layer, and a bottom of the trench is lower than the light emitting layer, as viewed in a cross-sectional view in a thickness direction of the flip chip light emitting diode.

5. The flip-chip light emitting diode of claim 1, wherein: the bottom of the trench is located on the substrate.

6. The flip chip light emitting diode of claim 1, wherein the semiconductor island structure is located in a center region of the flip chip light emitting diode.

7. The flip chip light emitting diode of claim 1, wherein the width of the upper surface of the semiconductor island structure is at least 30 μm.

8. The flip-chip led of claim 1, wherein the semiconductor island structure has an upper surface with a shape of a circle or a polygon.

9. The flip-chip led of claim 1, wherein the semiconductor island structure has a height that is less than or equal to a height of the semiconductor light emitting cell.

10. The flip-chip led of claim 1, further comprising a metal block located over the semiconductor island structure.

11. The flip-chip led of claim 10, wherein the metal block is in direct contact with an upper surface of the semiconductor island structure.

12. The flip-chip led of claim 10, wherein the metal block has a thickness of 0.5-10 μm.

13. The flip-chip led of claim 10, further comprising a protective layer covering at least the top surface and sidewalls of the semiconductor island structures.

14. The flip-chip led of claim 13, wherein the protective layer is located between the metal block and the semiconductor island structure or above the metal block.

15. The flip chip light emitting diode of claim 13 or 14, further comprising a first pad and a second pad;

16. The flip chip light emitting diode of claim 15, wherein neither the first nor the second pad is over the metal block.

17. The flip chip light emitting diode of claim 1, wherein the number of the semiconductor light emitting cells is 1.

18. The flip-chip led of claim 17, wherein the semiconductor light emitting cells surround the periphery of the semiconductor island structure.

19. The flip-chip light emitting diode of claim 1, wherein the number of the semiconductor light emitting cells is plural, and the plural semiconductor light emitting cells are arranged at intervals; the number of the semiconductor light emitting units is odd number or even number.

20. The flip-chip light emitting diode of claim 19, wherein the semiconductor island structures are located between adjacent semiconductor light emitting cells.

21. The flip chip light emitting diode of claim 19, wherein the semiconductor island structures are located between adjacent semiconductor light emitting cells at a central region of the flip chip light emitting diode.

22. The flip-chip led of claim 19, wherein adjacent semiconductor light emitting cells are electrically connected.

23. The flip chip light emitting diode of claim 1, wherein the width of the trench between the semiconductor island structure and the semiconductor light emitting cell increases from bottom to top.

24. A flip chip light emitting diode comprising:

a substrate;

the first and second semiconductor light-emitting units are positioned on the substrate and are semiconductor stacked layers, and each semiconductor stacked layer comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer;

25. The flip-chip light emitting diode of claim 24, wherein: the semiconductor stack layer of the second semiconductor light-emitting unit is locally concave.

26. The flip-chip light emitting diode of claim 24, wherein: the convex portion and the concave portion make the groove extend horizontally in a nonlinear shape between the adjacent semiconductor light emitting cells.

27. The flip-chip light emitting diode of claim 24, wherein: the convex part is positioned in the central area of the flip-chip light-emitting diode.

28. The flip chip light emitting diode of claim 24, wherein the width of the protruding portion is at least 30 μ ι η.

29. The flip-chip led of claim 25, wherein the protrusions and the recesses are cooperatively configured.

30. The flip chip light emitting diode of claim 24, wherein the edges of the protrusions are non-linear.

31. The flip chip light emitting diode of claim 24, wherein the edge of the protrusion is curved or connected by a plurality of line segments.

32. The flip-chip led of claim 24, wherein the protrusion has a thickness equal to a total thickness of the semiconductor stack.

33. The flip-chip light emitting diode of claim 24, further comprising an interconnection electrode connecting the first semiconductor light emitting cell and the second semiconductor light emitting cell.

34. The flip-chip led of claim 31, wherein the interconnection electrode is disposed on the bump.

35. The flip-chip led of claim 31, wherein the interconnection electrode is disposed on the bump.

36. The flip-chip led of claim 31, wherein the interconnect electrode is not located over the bump.

37. A light emitting device comprising the flip chip light emitting diode according to any one of claims 1 to 36.